1. Field of the Invention
The invention relates to a photocatalyst, and particularly relates to a composite photocatalyst, a manufacturing method thereof, a kit containing composite photocatalyst, and a bactericide photocatalyst.
2. Description of Related Art
Water scarcity is one of the top ten environmental issues faced by mankind in the 21st century. Wastewater recycling is one possible way to handle the water shortage problem, but effective treating methods for wastewater or sewage are especially needed. Theoretically, the wastewater treating methods can be divided into three categories by its principles: physical treatments, chemical treatments and biological treatments. Various wastewater treatment technologies, such as active carbon adsorption, chemical oxidation, biological treatments, ion exchange and thin film processes, are currently available. Chemical oxidation treatments are commonly used in the industries. Depending on the types of the oxidizing agents used, chemical oxidation treatments can be divided into four categories: air oxidation processes, ozone oxidation processes, chemical agent oxidation processes and advanced oxidation processes (AOP). The advanced oxidation processes recently draw a lot attentions because such treatment is not limited by the pollutant concentration(s) and has fast reaction rates. The main procedure of the advanced oxidation treatment is to generate hydroxyl free radicals of high oxidative capability to oxidize organic pollutants or materials for the removal of pollutants.
However, further improvements are needed for the currently used advanced oxidation processes, such as Fenton processes, ozone oxidation processes, high-efficiency electrolytic oxidation processes, wet oxidation processes or the photo-oxidation processes using titanium oxide (TiO2). Taking Fenton processes as the example, the iron sludge resulted from such processes is difficult to recycle and may lead to environmental pollutions. For the photo-oxidation processes using titanium oxide (TiO2), since TiO2 only absorbs lights in the ultraviolet wavelength for further reaction, such processes will be limited by the irradiation light wavelengths and the general light sources cannot be used, leading to very limited applications and ineffective results.